A method for removing a metal deposit from a surface in a chamber known from the state of the art includes the following steps:                a) a step in which the metal deposit is oxidised;        b) a step in which chemical species suitable for volatilising the oxidised metal deposit are injected, said second step b) being performed during at least part of step a).        
However, the effectiveness of such a removal method remains to be improved.
The chemical species suitable for volatilising the oxidised metal deposit may also react with the metal deposit prior to its oxidation. This is how step a) may be blocked.
The reaction of the chemical species with the metal deposit may therefore interfere with the removal method and above all compromise its effectiveness.
This is particularly the case when the removal method is performed to remove a copper (Cu) deposit from a surface in a chamber. Step a) generally includes the introduction of gaseous oxygen or gaseous ozone. Chemical species suitable for volatilising copper oxide include hexafluoroacetylacetone (hfacH). The hfacH chemical species also reacts with the copper before it is oxidised when the former is injected into the chamber. The oxidation reaction is then blocked.
The purpose of the present invention is therefore to propose a method for removing a metal deposit that makes it possible to limit interfering reactions, which are likely to block said method.
A first application of the invention relates to the cleaning of metal residues arranged on the inner walls of a deposition chamber.
Another application of the invention relates to the manufacturing of printed circuits and, more specifically, the etching of metal layers used, among others, for filling vias, which are metallised holes establishing electrical connection between several layers of a printed circuit.
Conventionally, the vias are filled in excess with a metal such as copper, so as to ensure satisfactory filling of the vias. The excess metal is removed by a chemomechanical etching step. A stop layer is arranged between the printed circuit substrate and the metal deposition layer to control the etching thickness. The chemomechanical etching step requires the use of stop layers to ensure very precise control of the method and further requires subsequent operations consisting in cleaning the etched surface, which is complex and expensive.
Another purpose of the invention is to propose a simplified and less expensive method for manufacturing metallised vias.